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What are the main performance differences between varchar and nvarchar SQL Server data types?
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Always use nvarchar.
You may never need the double-byte characters for most applications. However, if you need to support double-byte languages and you only have single-byte support in your database schema it's really expensive to go back and modify throughout your ap...
How do MySQL indexes work?
...xed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs to be useful - there's generally no point to index e.g. the frequency of the letter "L" per page.
share
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Clear terminal in Python [duplicate]
Does any standard "comes with batteries" method exist to clear the terminal screen from a Python script, or do I have to go curses (the libraries, not the words)?
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how to change an element type using jquery
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Here's one way you could do it with jQuery:
var attrs = { };
$.each($("b")[0].attributes, function(idx, attr) {
attrs[attr.nodeName] = attr.nodeValue;
});
$("b").replaceWith(function () {
return $("<h1 />", attrs).append($(this).con...
How do I import the Django DoesNotExist exception?
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You don't need to import it - as you've already correctly written, DoesNotExist is a property of the model itself, in this case Answer.
Your problem is that you are calling the get method - which raises the exception - before it...
How do I comment out a block of tags in XML?
How do I comment out a block of tags in XML?
7 Answers
7
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is it possible to change values of the array when doing foreach in javascript?
...f that second argument is not provided.
(Note: the above stuff about this does not apply if the callback is a => function, because this is never bound to anything when such functions are invoked.)
Also it's important to remember that there is a whole family of similar utilities provided on the ...
What is a difference between
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@Jon what do you mean by (In both cases E itself is okay.) in the first paragraph ?
– Geek
Jan 26 '13 at 8:47
2
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How to use Git Revert
...es are as if the bad update never occured:
cat README.md
Initial text
It doesn't matter where in the history the commit to be reverted is (in the above example, the last commit is reverted - any commit can be reverted).
Closing questions
do you have to do something else after?
A git revert is ju...
Hidden features of Perl?
...eric language features in Perl that you've actually been able to employ to do useful work?
78 Answers
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